A doubly-fed machine for propulsion applications

Abstract

A doubly fed machine for propulsion applications is proposed, which, given the presence of AC and DC power sources, can be utilized in order to improve efficiency, weight, volume, and sizing of the rotor power electronics. In this case, a shipboard application is examined. A hardware demonstration of a control architecture is implemented, along with a benchtop demonstration of the replacement of standard slip rings in the machine with a contactless solution (i.e. a transformer). Along with the benchtop demonstration of the transformer for accessing the rotor terminals, an analysis of the power handling capability of different converters for rectifying the power from the transformer for use with the electric machine is performed. A half bridge, full bridge, asymmetrical PWM half bridge, and asymmetrical PWM full bridge converter are all examined in terms of feasibility and power handling capability in simulation. A comparison of the modeled power transfer capability and the actual power handling capability of a half and a full bridge converter is also presented.